nitunit: conflicting name between modules and packages

[xymus]

nitunit fails to parse tests in the module lib/json/serialization.nit. There appears to be an importation conflict between json::serialization and ::serialization.

Error: conflicting module files for `serialization`: `lib/json/serialization.nit`, `/home/xymus/projects/nit/lib/serialization/serialization.nit

To reproduce, you need to first remove the nitish from existing tests/examples:

$ git diff
diff --git a/lib/json/serialization.nit b/lib/json/serialization.nit
index e26b8ec..5330b3d 100644
--- a/lib/json/serialization.nit
+++ b/lib/json/serialization.nit
@@ -35,9 +35,7 @@
 #
 # ### Usage Example
 #
-# ~~~nitish
-# import json::serialization
-#
+# ~~~
 # class Person
 #     serialize
 #

$ nitunit lib/json/serialization.nit
[KO] json::serialization
     lib/json/serialization.nit:39,3--69,0: Compilation error in nitunit.out/serialization-1.nit
    # class Person
      ^
     Output
    nitunit.out/serialization-1.nit:3,8--20: Error: conflicting module files for `serialization`: `lib/json/serialization.nit`, `/home/xymus/projects/nit/lib/serialization/serialization.nit`

==== Docunits of module json::serialization [X] tests: 1 KO: 1
Docunits: Entities: 49; Documented ones: 23; With nitunits: 1; Failures: 1
Test suites: Classes: 0; Test Cases: 0
[FAILURE] 1/1 tests failed.
`nitunit.out` is not removed for investigation.

[privat]

Docunits are collected and written as genuine nit source files.
However, nitunit assumes that the original module should be imported by these generated files, thus it injects a import originalmodule in the file, then invokes nitc.

The invoked nitc see the import originalmodule and have to find it. Problem: the generated file in a subdirectory unrelated to the originalmodule or its package so it cannot find it.
To solve this problem, nitunit just add a -I directoryof(originalmodule) to the nitc invocation, so nitc can look for the originalmodule in its pathib.

Unfortunately nitc fails and insults you if there is conflicts for modules accessible from the pathlib. lib/serialization is by default in the pathlib, and lib/json/serialization.nit was added thanks to the -I.

Some solutions:

• stop injecting -I and force the programmer to always add the import in its nitunit

  PRO: no more conflict

  CON: a lot more module not found and angry programmers

• inject a full path import, not a relative one. eg import json::serialization

  PRO: simple & better than now

  CON: won't work if the package of the module is not in the pathlib

• same plus inject -I directory(package(othermodule))

  PRO: simple & better than now

  CON: might cause similar issue if the directory of the package contains crap that
  might conflict (not perfect solution)

• extends the language to import a fixed file. eg import "lib/json/serialization.nit"

  PRO: simple

  CON/PRO?: C-like

  CON: need to extends the grammar and regenerate the parser